﻿<p>The <em>IfcPolyline</em> is a bounded curve with only linear segments defined by a list of Cartesian points. If the first and the last Cartesian point in the list are identical, then the polyline is a closed curve, otherwise it is an open curve.</p> 

<blockquote class="example">EXAMPLE&nbsp; Figure 2 illustrates a bounded <i>IfcPolyline</i> and shows the parametric length of each segment and of the total polyline. The parametric length of the entire polyline is <em>n</em> - 1, where <em>n</em> is the number of <em>Points</em>.</blockquote>
<table summary="illustration">
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<td style="vertical-align:top;"><img src="../../../figures/ifcpolyline-fig1.png" alt="polyline examples"></td>
</tr>
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<td><p class="figure">Figure 2 &mdash; Bounded <em>IfcPolyline</em> with parametric length</p></td>
</tr>
</table>

<blockquote class="extDef">
NOTE&nbsp; Definition according to ISO/CD 10303-42:1992<br>
A polyline is a bounded curve of <em>n</em> - 1 linear segments, defined by a list of <em>n</em> points, P<sub>1</sub>, P<sub>2</sub> ... P<sub>n</sub>. The <em>i</em> <sup>th</sup> segment of the curve is parameterized as follows:
<blockquote class="extDef">
<img src="../../../figures/ifcpolyline-math1.gif" width="190" height="24" align="middle">&nbsp;&nbsp;&nbsp;
<em>for</em> 1 &le; <em>i</em> &le; <em>n</em> - 1
</blockquote>
where <em>i</em> - 1 &le; <em>u</em> &le; <em>i</em> and with parametric range of 0 &le; <em>u</em> &le; <em>n</em> - 1.
</blockquote>
<blockquote class="note">NOTE&nbsp; Entity adapted from <strong>polyline</strong> in ISO 10303-42.</blockquote>

<blockquote class="history">HISTORY&nbsp; New entity in IFC1.0</blockquote>